Along with the drastic development of intelligent electronic products in recent years, touch screens and touch-sensitive buttons have been extensively applied to a plurality of electronics and other relevant products. By virtue of their characteristics of having a visualized human-machine interface, being easy to operate and to define virtually, these products have more humanized operations and more diverse functions. The applications of touch screens and touch buttons become wider and wider. These products are required to have more functionalities and high reliability, in order to be applicable to more circumstances. Existing touch screens and touch buttons are of various types, such as capacitive, resistive, infrared or surface acoustic touch screens or touch buttons. By detecting the variations of capacitances, resistances, infrared signals, and/or surface acoustic waves before and after each touch operation, these touch button or touch screens are able to identify touched positions. However, practically, such touch devices have certain limitations, such as low reliability, being unable to detect pressure values, specific input mechanism, and restricted applications in conductive mediums, for example, metal, and so on.
To solve the problem, there exists a pressure-sensitive touch button or touch screen, which has high reliability and flexible input mechanisms, is applicable to any elastic medium, and can detect pressure values. Thus, it can be used in a touch control apparatus with high requirements. However, since a pressure sensing touch screen or touch button detects a pressed position and a pressure value by detecting the strain of a medium, it is limited by the strength and thickness of the medium, for example, if the medium is thick and strong, it would be hard to detect a gentle touch operation. As a result, a detected touch operation may not be smooth.